#include "csapp.h"
int main(int argc，char **argv)
{
    struct addrinfo *p，*listp, hints
        char buf[MAXLINE];
    int rc，flags;
    if (argc != 2)
    {
        fprintf(stderr，"usage:}s <domain name>\n"，argv [0])
        exit (0);
    }
    /*Get a list of addrinfo records*/
    memset(&hints，0，sizeof(struct addrinfo));
    hints.ai_family=AF_ INET;/*IPv4 only*/
    hints.ai_socktype=SOCK_STREAM;/*Connections only*/
    if((rc=getaddrinfo(argv[1]，NULL，&hints，8tlistp))l=0)
    {
        fprintf(stderr, "getaddrinfo error:}s\n"，gai_strerror(rc))
        exit (1);
    }
    /*Walk the list and display each IP address*/
    flags=NI NUMERICHOST;/*Display address string instead of domain name*/
    for  (p=listp; p; P=p->ai next)
    {
        Getnameinfo(p->ai_addr，p->ai-addrlen, buf，MAXLINE, NULL, 0，flags);
        printf("%s\n"，buf );
    }
    /*Clean up*/
    Freeaddrinfo(listp);
    exit (0)
}
